Book-Level Overview

Physics instructors are working with ExpertTA to create an updated and enhanced version of the OpenStax University Physics (OSUP) calculus-based textbook. This updated version maintains the structure of the original to ease the transition for instructors and follows the approach of many of the best-selling university physics texts. Changes span all chapters. These changes include enhancing content to ensure completeness, consistency, and correctness of physics concepts, emphasizing fundamental principles over obscure details, clarifying definitions and explanations, and simplifying advanced mathematical sections to be understandable for today’s students. The authors use improved approaches to problem-solving by adopting a consistent, more expert-like methodology and incorporating figures, diagrams, and graphs throughout to enhance understanding. Notation and formatting are standardized across the chapters and in figures. Many of the figures have been updated for clarity. There are numerous chapter-specific revisions (available upon request) that address overly lengthy or confusing sections, refine key concepts, and provide more relevant examples. Overall, these updates make the textbook more accessible, consistent, and pedagogically effective for introductory physics students.

Chapter 1 – Measurement and Problem Solving

The chapter has been shortened to be more student friendly, while retaining important topics. The explanation of the scientific process provides a better description of how science is carried out as a profession. Greater emphasis has been placed on modeling and its role across science and engineering, so that it is understood that models have ranges of applicability and are simplifications of actual physical phenomena. The sections on units, physical quantities, dimensions, and unit conversion have been better defined. Section 1.5 includes a concise discussion on accuracy and significant figures and briefly covers significant figures in math operations. The final sections highlight the practical importance of estimations and provide detailed problem-solving guidance, prioritizing qualitative tools such as diagrams and graphs over equation-centric approaches. The “Solution” step has been reformulated to favor algebraic reasoning with variables over numerical calculations, emphasizing that this method promotes result-checking and enables exploration of limits and parameter changes—key learning objectives in physics.

Chapter 2 – Vectors

The focus is shifted from graphical and geometric vector methods to coordinate-based approaches. The “tip-to-tail” method for vector addition is briefly introduced and figures have been improved for clarity. Discussions of unit vectors are relocated to Section 2.2, and subscripts are introduced to denote displacement start and end points. Positions defined relative to a coordinate system are used for displacement calculations. Problem-solver discretion is also introduced when choosing coordinate systems. Confusion between vector and scalar components has been removed through clear definition and consistent use. Vector component determination using trigonometry is introduced with ample examples. The discussion of vector addition and subtraction is simplified and reorganized into topical subsections with more practical examples with clearly drawn figures. The chapter concludes with vector multiplication with separate discussions on scalar and vector products. Examples that include content from future chapters have been removed. There are improved right-hand rule illustrations using standard approaches and better visuals.

Chapter 3 – Motion Along a Straight Line

Revisions have been made to enhance student understanding of kinematics through improved consistency and clarity. Use of qualitative representations, such as motion diagrams and graphs, have been added. Application of vectors in one-dimensional motion is clearly demonstrated through examples. Kinematic variables are clearly defined. The notation for time dependence has been clarified to distinguish between general functions like x(t) and specific position values, such as x_i and x_f. Some examples now incorporate non-zero initial values to better illustrate real-world scenarios with changes in acceleration. Section 3.2 expands on average and instantaneous velocity with improved examples. In Section 3.4, constant acceleration is presented as a practical model with both useful applications and limitations. The local gravitational constant, g, is defined as the magnitude of the near-Earth gravitational field rather than the “acceleration due to gravity”, with the free-fall model being the approximation that a_y = -g being applicable in some cases. The equations of kinematics are shown to all describe the same motion, emphasizing conceptual understanding in problem solving, and discouraging mindless equation hunting. Recognition is made that not all students are at the same place in their knowledge of calculus, limiting the use of more advanced mathematics. Physically grounded problems replace abstract examples, ensuring accessibility and relevance. These changes are meant to bridge mathematical rigor with physical intuition to make the text more engaging.

Chapter 4 – Motion in Two and Three Dimensions

Several pedagogical enhancements have been made to improve clarity and conceptual understanding. Beginning in Section 4.1, units are now explicitly required for numerical vector components and physical variables are emphasized to carry implicit units. The concept of force is briefly introduced to help explain the independence of motion in orthogonal directions. Examples prioritize everyday physics and correct unit usage. Cartesian unit vectors are reintroduced and applied. Section 4.3 expresses projectile motion as an approximate model. Kinematic equations for free-fall motion consistently use a_y = -g. In Section 4.4, uniform circular motion is more clearly defined. Angular velocity is used rather than “angular frequency.” Section 4.5 improves definitions of reference frames with better images, introduces relatable relative motion illustrations, and ensures consistent subscript conventions for vectors in different reference frames.

Chapter 5 – Newton’s Laws of Motion

The chapter prioritizes a systems-based approach, emphasizing external forces, interaction pairs, and consistent use of free body diagrams (FBDs) in all problem setups. Newton’s Laws are presented as applicable within classical parameters, avoiding the misleading terms, such as “universal law,” and by directly addressing non-Newtonian misconceptions. In Section 5.1, systems and external forces are introduced early, the particle model introduced in earlier chapters (neglecting internal motion and rotation) is used alongside the basic concept of the center of mass. Detailed rules for using free-body diagrams are introduced. Consistent vector notation and component analysis are used throughout. Section 5.2 reframes Newton’s First Law to focus on constant velocity as natural motion and the meaning and importance of inertial reference frames (IRFs). The description of inertia is carefully worded to avoid common points of confusion. Section 5.3 presents Newton’s Second Law (a = F/m) as an experimentally validated relation. Section 5.4 defines weight as the gravitational force and mass as a fundamental property of objects. The scalar constant g is defined as the magnitude of a vector field strength to avoid incorrect use of g as an acceleration. Universal Gravitation is briefly introduced to explain variations in g. Section 5.5 will demonstrate careful problem solving for forces with clear definitions of systems and external forces. No distinction is made between problems with zero and non-zero acceleration, as Newton’s Second Law is correctly applied to both. The revised physics content is rewritten for clarity and pedagogical accuracy that emphasizes that Newton’s First and Second Laws apply to single objects or systems, while Newton’s Third Law governs interactions between pairs of objects. Precise vector notation (e.g., F_{A on B} = −F_{B on A}) is used in Newton’s Third Law problems. Misleading terms like “action/reaction” are avoided as it can result in incorrect ideas of cause and effect. This restructuring ensures a technically precise, cohesive framework for understanding Newtonian mechanics.

Chapter 6 – Applications of Newton’s Laws

The revised content introduces a rigorous, consistent approach to problem-solving, emphasizing clear free body diagrams (FBDs) and analytical solutions with thorough checks for correctness, including units and limiting cases. The chapter highlights problem-solving strategies, friction models, and circular motion. The misleading term “centripetal force” to avoided clarify that there is not some new force and emphasize that centripetal acceleration results from the component of the net force (sum of all external forces) towards the center of circular motion. Identification of physical principles is emphasized along with carefully constructed FBDs. Section 6.2, split into kinetic and static friction subsections, explains our description of friction as a phenomenological model determined by relative sliding motion between two objects, or potential sliding, and not the center of mass motion. Misconceptions about static versus kinetic friction coefficients are corrected. Section 6.3, retitled “Forces and Circular Motion,” emphasizes that circular motion problems are another application of Newton’s second law, with expanded examples (e.g., pendula, amusement park rides, banked curves with friction). This is not new physics. Section 6.4 simplifies the use of drag force models and limits the application of differential equations. Some problematic examples are revised, relocated, or removed to align with students’ mathematical backgrounds. More advanced mathematics is separated from standard content and clearly identified.

Chapter 7 – Work and Kinetic Energy

The chapter has been revised for clarity and to emphasize the fundamental nature of work and kinetic energy. Systems are now explicitly discussed, defining work solely as energy transfer due to external forces. Confusing references to “work done against” forces or by systems is removed. We motivate the concepts of work and kinetic energy using Newton’s second law, starting with 1D particle models (e.g., a block sliding down a frictionless slope) before extending to 3D, with simplified dot product explanations and clear distinctions between the work done by individual forces versus the net work done by all external forces. Potentially misleading statements, like the normal force doing no work in all cases, have been corrected and problematic examples revised or replaced. The section on conservative and non-conservative forces has been moved from chapter 8 and is now Section 7.2. The Work-Kinetic Energy theorem is now termed the Center of Mass Work-Kinetic Energy theorem to emphasizes its limited applicability to the center-of-mass motion of particles, and not to systems with internal interactions or motion. Conservative forces are introduced via gravity and springs, with vector calculus minimized. Sections 7.2 and 7.3 are merged for a cohesive kinetic energy definition, and power is reframed to focus on work as energy exchange. These changes aim to provide a clearer, more physically grounded presentation for students.